Unique in approach and content, this text presents the theory of finite element analysis, explores its application as a design/modeling tool, and explains in detail how to use ANSYS intelligently and effectively.

New To This Edition

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New chapters on matrix algebra, beams and frames, dynamic problems, and design and material selection. Helps students understand how a system of nodal equations are solved.

New sections on axisymmetric elements and formulations, p-method and h-method, and unsteady heat transfer. Two new appendices-Covering properties of area shapes and properties of structural steel shapes.Helps students refresh their understanding of properties of area shapes, a review of first and second moments of area are provided in appendix C.

Integration of ANSYS 6.1 (the latest version) throughout-Each chapter first discusses the relevant basic theory and then demonstrates it using simple problems with hand-calculations. Follows with examples that are solved using ANSYS.Helps students learn how to use ANSYS quickly and effectively. Shows students how to use ANSYS step by step to model a physical problem.

Features and Benefits

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NEW - New chapters on matrix algebra, beams and frames, dynamic problems, and design and material selection. Helps students understand how a system of nodal equations are solved.

NEW - New sections on axisymmetric elements and formulations, p-method and h-method, and unsteady heat transfer. NEW - Two new appendices-Covering properties of area shapes and properties of structural steel shapes.Helps students refresh their understanding of properties of area shapes, a review of first and second moments of area are provided in appendix C.

NEW - Integration of ANSYS 6.1 (the latest version) throughout-Each chapter first discusses the relevant basic theory and then demonstrates it using simple problems with hand-calculations. Follows with examples that are solved using ANSYS.Helps students learn how to use ANSYS quickly and effectively. Shows students how to use ANSYS step by step to model a physical problem.

Discussions of various sources of error that can contribute to wrong results-Devotes a section, at the end of each selected chapter, to verifying ANSYS results.Emphasizes for students how to find suitable ways to verify Finite Element Analysis (FEA) findings.

Open-ended design problems. Exposes students to many design problems that could be solved with ANSYS.

A brief review of fundamental principles in solid mechanics, heat transfer, and fluid mechanics. Helps students keep these important concepts fresh in their minds.

Mechanical and thermophysical properties of some common materials used in engineering-Covered in appendices. A list of objectives and a summary for each chapter. Gives students a preview of what they can expect to learn at the beginning of each chapter and a concise overview of the lessons learned at the end of each chapter.

Table of Contents

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1. Introduction.

2. Matrix Algebra.

3. Trusses.

4. Axial Members, Beams, and Frames.

5. One-Dimensional Elements.

6. Analysis of One-Dimensional Problems.

7. Two-Dimensional Elements.

8. More ANSYS.

9. Analysis of Two-Dimensional Heat Transfer Problems.

10. Analysis of Two-Dimensional Solid Mechanics Problems.

11. Dynamic Problems.

12. Analysis of Fluid Mechanic Problems.

13. Three-Dimensional Elements.

14. Design and Material Selection.

15. Design Optimization.

Appendix A: Mechanical Properties of Some Materials.

Appendix B: Thermophysical Properties of Some Materials.

Appendix C: Properties of Common Area Shapes.

Appendix D: Properties of Structural Steel Shapes.

Appendix E: Conversion Factors.

Index.

Preface

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The second edition of Finite Element Analysis, consisting of 15 chapters, includes a number of new features and changes that were incorporated in response to suggestions and requests made by professors, students, and professionals using the first edition of the book. The major features include:

A new comprehensive chapter on matrix algebra A new chapter on beams and frames New sections on axisymmetric elements and formulations A new section on p-method and h-method A new section on unsteady heat transfer A new chapter on dynamic problems A new chapter on design and material selection Two new appendices with properties of area shapes and properties of structural steel shapes A new appendix with examples of batch files A web site to offer additional information for instructors and students Moreover, a large number of problems have been added, and the property tables have been expanded. I hope you enjoy the second edition.

There are many good textbooks already in existence that cover the theory of finite element methods for advanced students. However, none of these books incorporate ANSYS as an integral part of their materials to introduce finite element modeling to undergraduate students and newcomers. In recent years, the use of finite element analysis as a design tool has grown rapidly. Easy-to-use, comprehensive packages such as ANSYS, a general-purpose finite element computer program, have become common tools in the hands of design engineers. Unfortunately, many engineers who lack the proper training or understanding of the underlying concepts have been using these tools. This introductory book is written to assist engineering students and practicing engineers new to the field of finite element modeling to gain a clear understanding of the basic concepts. The text offers insight into the theoretical aspects of finite element analysis and also covers some practical aspects of modeling. Great care has been exercised to avoid overwhelming students with theory, yet enough theoretical background is offered to allow individuals to use ANSYS intelligently and effectively. ANSYS is an integral part of this text. In each chapter, the relevant basic theory is discussed first and demonstrated using simple problems with hand calculations. These problems are followed by examples that are solved using ANSYS. Exercises in the text are also presented in this manner. Some exercises require manual calculations, while others, more complex in nature, require the use of ANSYS. The simpler hand-calculation problems will enhance students' understanding of the concepts by encouraging them to go through the necessary steps in a finite element analysis. Design problems are also included at the end of Chapters 3, 4, 6, and 9 through 14.

Various sources of error that can contribute to incorrect results are discussed. A good engineer must always find ways to check the results. While experimental testing of models may be the best way, such testing may be expensive or time consuming. Therefore, whenever possible, throughout this text emphasis is placed on doing a 'sanity check' to verify one's finite element analysis (FEA). A section at the end of each appropriate chapter is devoted to possible approaches for verifying ANSYS results.

Another unique feature of this book is that the last two chapters are devoted to the introduction of design, material selection, optimization, and parametric programming with ANSYS.

The book is organized into 15 chapters. Chapter 1 reviews basic ideas in finite element analysis. Common formulations, such as direct, potential energy, and weighted residual methods are discussed. Chapter 2 provides a comprehensive review of matrix algebra. Chapter 3 deals with the analysis of trusses, because trusses offer economical solutions to many engineering structural problems. An overview of the ANSYS program is given in Chapter 3 so that students can begin to use ANSYS right away. Finite element formulation of members under axial loading, beams, and frames are introduced in Chapter 4. Chapter 5 lays the foundation for analysis of one-dimensional problems by introducing one-dimensional linear, quadratic, and cubic elements. Global, local, and natural coordinate systems are also discussed in detail in Chapter 5. An introduction to isoparametric formulation and numerical integration by Gauss-Legendre formulae are also presented in Chapter 5. Chapter 6 considers Galerkin formulation of one-dimensional heat transfer and fluid problems. Two-dimensional linear and higher order elements are introduced in Chapter 7. Gauss-Legendre formulae for two-dimensional integrals are also presented in Chapter 7. In Chapter 8 the essential capabilities and the organization of the ANSYS program are covered. The basic steps in creating and analyzing a model with ANSYS is discussed in detail. Chapter 9 includes the analysis of two-dimensional heat transfer problems with a section devoted to unsteady situations. Chapter 10 provides analysis of torsion of noncircular shafts and plane stress problems. Dynamic problems are explored in Chapter 11. Review of dynamics and vibrations of mechanical and structural systems are also given in this chapter. In Chapter 12, two-dimensional, ideal fluid-mechanics problems are analyzed. Direct formulation of the piping network problems and underground seepage flow are also discussed. Chapter 13 provides a discussion of three-dimensional elements and formulations. This chapter also presents basic ideas regarding top-down and bottom-up solid modeling methods. The last two chapters of the book are devoted to design and optimization ideas. Design process and material selection are explained in Chapter 14. Design optimization ideas and parametric programming are discussed in Chapter 15. Each chapter begins by stating the objectives and concludes by summarizing what the reader should have gained from studying that chapter.

The examples that are solved using ANSYS show in great detail how to use ANSYS to model and analyze a variety of engineering problems. Chapter 8 is also written such that it can be taught right away if the instructor sees the need to start with ANSYS.

A brief review of appropriate fundamental principles in solid mechanics, heat transfer, dynamics, and fluid mechanics is also provided throughout the book. Additionally, when appropriate; students are warned about becoming too quick to generate finite element models for problems for which there exist simple analytical solutions. Mechanical and thermophysical properties of some common materials used in engineering are given in appendices A and B. Appendices C and D give properties of common area shapes and properties of structural steel shapes, respectively. Examples of ANSYS batch files are given in Appendix F.

Finally, a Web site at http://www.prenhall.com/Moaveni will be maintained for the following purposes: (1) to share any changes in the upcoming versions of ANSYS; (2) to share additional information on upcoming text revisions; (3) to provide additional homework problems and design problems; and (4) although I have done my best to eliminate errors and mistakes, as is with most books, same errors may still exist. I will post the corrections that are brought to my attention at the site. The Web site will be accessible to all instructors and students.